[ Impact de la faille des lagunes sur la genèse des grès bitumineux du Sud-Est de la Côte d’Ivoire : Aspect lithologique et environnemental ]
Volume 43, Issue 2, July 2019, Pages 99–111
Fori Yao Paul Assale1, ANO Nyamekai François d’Assise2, KESSE Touvalé Marcel3, KPLOHI Yaba Hervé4, KOUAO Assié François5, TAHE Thierry6, and COULIBALY Aoua7
1 Laboratoire de Géologie Marine et de Sédimentologie, Université Félix Houphouët-Boigny (UFHB), Abidjan, Côte d’Ivoire
2 Université Félix Houphouët Boigny, UFR des Sciences de la Terre et des Ressources Minières, Abidjan, Côte d’Ivoire
3 Institut National Polytechnique Houphouët Boigny, Yamoussoukro, Côte d’Ivoire
4 PETROCI, Centre d’Analyses et de Recherche (CAR), Abidjan, Côte d’Ivoire
5 Université Félix Houphouët Boigny, UFR des Sciences de la Terre et des Ressources Minières, Abidjan, Côte d’Ivoire
6 PETROCI, Centre d’Analyses et de Recherche (CAR), Abidjan, Côte d’Ivoire
7 Université Félix Houphouët Boigny, UFR des Sciences de la Terre et des Ressources Minières, Abidjan, Côte d’Ivoire
Original language: French
Copyright © 2019 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The trace of the Lagoons’ Fault permitted to understand the distribution of bitumen in the onshore sedimentary basin in South-east of Ivory Coast. The bituminous formations met are made up mainly of bituminous sandstone which are sometimes associated with other bituminous formations (microconglomerats, sands, kaolins, glaucony, marly limestones and fossiliferous rocks). The bituminous sandstones are quartz wackes resulting from the consolidation of old quartzose sands by the bitumen. There are nano-vacuums between the grains quartz and the bitumen of these sandstones. This bitumen comes from the hydrocarbons which were formed in South of the Lagoons’ Fault in the surroundings of Eboïnda. They were spread by diffusion through paleo-beaches and communicating paleo-channels before reaching the layout of the Lagoons’ Fault and its satellite faults. It is thanks to these faults and to other communicating paleo-channels that the bitumen could migrate to North of the Lagoons’ Fault between Samo and Grand-Bassam even beyond on a distance of at least 75 km. The bitumen is trapped in the form of lenses in fluviatile paleo-channels and paleo-beaches located between Eboïnda and Grand-Bassam. The migration was done from East to West. The bituminous sandstones are in outcrop, subsurfaces and in the sublagoonals; that involves a contamination of soils, phreatic water table and lagoons surrounding.
Author Keywords: Sandstone, bitumen, lenses, Lagoons’ Fault, Ivory Coast.
Volume 43, Issue 2, July 2019, Pages 99–111
Fori Yao Paul Assale1, ANO Nyamekai François d’Assise2, KESSE Touvalé Marcel3, KPLOHI Yaba Hervé4, KOUAO Assié François5, TAHE Thierry6, and COULIBALY Aoua7
1 Laboratoire de Géologie Marine et de Sédimentologie, Université Félix Houphouët-Boigny (UFHB), Abidjan, Côte d’Ivoire
2 Université Félix Houphouët Boigny, UFR des Sciences de la Terre et des Ressources Minières, Abidjan, Côte d’Ivoire
3 Institut National Polytechnique Houphouët Boigny, Yamoussoukro, Côte d’Ivoire
4 PETROCI, Centre d’Analyses et de Recherche (CAR), Abidjan, Côte d’Ivoire
5 Université Félix Houphouët Boigny, UFR des Sciences de la Terre et des Ressources Minières, Abidjan, Côte d’Ivoire
6 PETROCI, Centre d’Analyses et de Recherche (CAR), Abidjan, Côte d’Ivoire
7 Université Félix Houphouët Boigny, UFR des Sciences de la Terre et des Ressources Minières, Abidjan, Côte d’Ivoire
Original language: French
Copyright © 2019 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
The trace of the Lagoons’ Fault permitted to understand the distribution of bitumen in the onshore sedimentary basin in South-east of Ivory Coast. The bituminous formations met are made up mainly of bituminous sandstone which are sometimes associated with other bituminous formations (microconglomerats, sands, kaolins, glaucony, marly limestones and fossiliferous rocks). The bituminous sandstones are quartz wackes resulting from the consolidation of old quartzose sands by the bitumen. There are nano-vacuums between the grains quartz and the bitumen of these sandstones. This bitumen comes from the hydrocarbons which were formed in South of the Lagoons’ Fault in the surroundings of Eboïnda. They were spread by diffusion through paleo-beaches and communicating paleo-channels before reaching the layout of the Lagoons’ Fault and its satellite faults. It is thanks to these faults and to other communicating paleo-channels that the bitumen could migrate to North of the Lagoons’ Fault between Samo and Grand-Bassam even beyond on a distance of at least 75 km. The bitumen is trapped in the form of lenses in fluviatile paleo-channels and paleo-beaches located between Eboïnda and Grand-Bassam. The migration was done from East to West. The bituminous sandstones are in outcrop, subsurfaces and in the sublagoonals; that involves a contamination of soils, phreatic water table and lagoons surrounding.
Author Keywords: Sandstone, bitumen, lenses, Lagoons’ Fault, Ivory Coast.
Abstract: (french)
Le tracé de la Faille des Lagunes a permis de comprendre la distribution du bitume dans le bassin sédimentaire onshore au Sud-Est de la Côte d’Ivoire. Les formations bitumineuses rencontrées sont constituées principalement de grès bitumineux auxquels sont parfois associées d’autres formations bitumineuses (microconglomérats, sables, kaolins, glauconie, calcaires marneux et roches fossilifères). Les grès bitumineux sont des quartz wackes issus de la consolidation d’anciens sables quartzeux par le bitume. Il existe des nano-vides entre les grains de quartz et le bitume de ces grès. Ce bitume provient des hydrocarbures qui ont été formés au Sud de la Faille des Lagunes dans les environs d’Éboïnda. Ils se sont répandus par diffusion à travers des paléo-plages et des paléo-chenaux communicants avant d’atteindre le tracé de la Faille des Lagunes et ses failles satellites. C’est grâce à ces failles et à d’autres paléo-chenaux communicants que le bitume a pu migrer au Nord de la Faille des Lagunes entre Samo et Grand-Bassam voire au-delà sur une distance de 75 km au moins. Le bitume est piégé sous forme de lentilles dans des paléo-chenaux fluviatiles et paléo-plages situés entre Éboïnda et Grand-Bassam. Les grès bitumineux sont en affleurement, en sub-surfaces et dans des sous-sols lagunaires ; ce qui entraine une contamination des sols, des nappes phréatiques et des lagunes environnants.
Author Keywords: Grès, Bitume, lentille, faille des lagunes, Côte d’Ivoire.
How to Cite this Article
Fori Yao Paul Assale, ANO Nyamekai François d’Assise, KESSE Touvalé Marcel, KPLOHI Yaba Hervé, KOUAO Assié François, TAHE Thierry, and COULIBALY Aoua, “The Lagoons’ Fault impact on the genesis of bituminous sandstones of south-east of the Ivory Coast: Lithological and environmental aspect,” International Journal of Innovation and Scientific Research, vol. 43, no. 2, pp. 99–111, July 2019.
